As data service requirements rapidly grow, and a data carrying capability of a 2G/3G (second-generation/third-generation) wireless network is limited, offloading a data service by using a Wireless Local Area Network (WLAN) has become a preferred solution of an operator.
A WLAN technology-based network structure generally includes devices such as a station (STAtion, STA for short), an Access Point (AP), and an Access Controller (AC). A function of the AP is to connect the STA to a wired network, and the AC manages the AP by using the Control and Provisioning of Wireless Access Points (CAPWAP) protocol. Generally, a CAPWAP tunnel is established between the AP and the AC as a forwarding channel of control and data packets between the AP and the AC.
However, by means of the prior art, when an AC and a Broadband Remote Access Server (BRAS) are disposed separately, because all user data needs to be forwarded by the AC, overheads of the AC are increased, and in an existing AC networking manner, a large quantity of site Virtual Local Area Networks (VLANs) need to be configured between the AC and the BRAS to acquire binding relationships between different APs and different BRASs. Therefore, by means of the prior art, workload and costs of configuration, management, and maintenance of the AC are greatly increased.